The magnetic phase diagram of Gd₂Sn₂O₇

Measurements of the magnetic susceptibility of the frustrated pyrochlore magnet Gd₂Sn₂O₇ have been performed at temperatures below T = 5K and in magnetic fields up to H = 12T. The phase boundaries determined from these measurements are mapped out in an H-T phase diagram. In this gadolinium compound, where the crystal-field splitting is small and the exchange and dipolar energy are comparable, the Zeeman energy overcomes these competing energies, resulting in at least four magnetic phase transitions below 1K. These data are compared against those for Gd₂Ti ₂O₇ and will, we hope, stimulate further studies.